A) They busy and want you to stop talking to them.
B) They're in the presence of someone they really like and want you to stop talking to them.
C) They think you're coming onto them and want you to stop talking to them.
D) They want you to stop talking to them.

It's funny cuz my best friend would do the same thing so i completely stop talking to her for the rest of the day then she sometimes gets upset cuz I'm not talking to her.
Well whenever i do try to talk I get one worded answers and idk about u but when i talk to people I like to have an actual conversation.